Hepatitis B virus mutation pattern rtA181S+T184I+M204I may contribute to multidrug resistance in clinical practice: Analysis of a large cohort of Chinese patients

The role of Traditional Chinese medicine in anti-HBV: background, progress, and challenges

Chronic hepatitis B (CHB) remains a major world's most serious public health issues. Despite the remarkable effect of nucleos(t)ide analogues (NAs) in inhibiting hepatitis B virus (HBV) deoxyribonucleic acid (DNA) as the first-line drug, there are several limitations still, such as poor antigen inhibition, drug resistance, low-level viremia, restricting patients' functional cure. Due to the constraints of NAs, traditional medicines, such as traditional Chinese medicine (TCM), have become more prevalently used and researched in the clinical treatment of CHB as complementary alternative therapies. As a consequence, the review focuses on the background based on HBV's life cycle as well as the NAs' limitations, progress based on direct and indirect pathway of targeting HBV of TCM, and challenges of TCM. We found TCMs play an increasingly important role in anti-HBV. In a direct antiviral way, they regulate HBV infection, replication, assembly, and other aspects of the HBV life cycle. As for indirect way, TCMs can exert anti-HBV effects through targeting the host, including immune regulation, apoptosis, autophagy, oxidative stress, etc. Especially, TCMs have the advantages of strong antigenic inhibition compared to NAs. Specifically, we can combine the benefits of TCMs in strong HBV antigen inhibition with the benefits of NAs in targeted antiviral effects, in order to find a suitable combination of "TCM + NAs" to contribute to Chinese knowledge of the realisation of the "global elimination of HBV by 2030" goal of the World Health Organization.

ViMRT: a text-mining tool and search engine for automated virus mutation recognition

MOTIVATION

Virus mutation is one of the most important research issues which plays a critical role in disease progression and has prompted substantial scientific publications. Mutation extraction from published literature has become an increasingly important task, benefiting many downstream applications such as vaccine design and drug usage. However, most existing approaches have low performances in extracting virus mutation due to both lack of precise virus mutation information and their development based on human gene mutations.

RESULTS

We developed ViMRT, a text-mining tool and search engine for automated virus mutation recognition using natural language processing. ViMRT mainly developed 8 optimized rules and 12 regular expressions based on a development dataset comprising 830 papers of 5 human severe disease-related viruses. It achieved higher performance than other tools in a test dataset (1662 papers, 99.17% in F1-score) and has been applied well to two other viruses, influenza virus and severe acute respiratory syndrome coronavirus-2 (212 papers, 96.99% in F1-score). These results indicate that ViMRT is a high-performance method for the extraction of virus mutation from the biomedical literature. Besides, we present a search engine for researchers to quickly find and accurately search virus mutation-related information including virus genes and related diseases.

AVAILABILITY AND IMPLEMENTATION

ViMRT software is freely available at http://bmtongji.cn:1225/mutation/index.

Investigation of multidrug-resistance mutations of hepatitis B virus (HBV) in a large cohort of chronic HBV-infected patients with treatment of nucleoside/nucleotide analogs

Multidrug-resistance hepatitis B virus (MDR HBV), defined as those with mutations resistant to both nucleoside analogs lamivudine/telbivudine/entecavir (LAM/LdT/ETV) and nucleotide analog adefovir (ADV), has potential to cause treatment difficulty. To clarify clinical prevalence and virological features of MDR HBV, we investigated serum samples from 28,236 chronic HBV-infected patients with treatment of nucleoside/nucleotide analogs. All patients underwent resistance testing in the Fifth Medical Center of Chinese PLA General Hospital between 2007 and 2019. MDR mutations were screened by direct sequencing; MDR strains (with mutations co-located on the same viral genome) were verified by clonal sequencing (≥20 clones/sample) and subjected to phenotypic analysis if necessary. MDR mutations were detected in 0.81% (229/28,236) patients. MDR strains were verified in 83.0% (190/229) of MDR mutation-positive patients. As ETV-resistance mutation (ETVr) had additional mutation(s) on LAMr conferring more resistance, MDR mutations fell into LAMr + ADVr and ETVr + ADVr subsets. Sixteen mutation patterns of MDR strains were verified, including eight with LAMr + ADVr and eight with ETVr + ADVr. Refractory to sequential therapies of LAM/LdT/ETV and ADV were closely linked with MDR HBV development. Ten representative MDR strains (five LAMr + ADVr and five ETVr + ADVr) tested all had decrease in replication capacity compared to wild-type strains and decrease extent was positively related with the number of primary resistance on viral genome. Compared to ADV + ETV, TDF/TDF + ETV showed higher inhibitory rates on MDR HBV, especially for the five ETVr + ADVr strains (74.5%-97.6% vs. 60.2%-79.5%, all P < 0.05). This study significantly extends the knowledge on MDR HBV and has clinical implications for resistance management.

Long-term efficacy and safety of nucleos(t)ides analogues in patients with chronic hepatitis B

Nucleos(t)ide analogues with high barrier to resistance are regarded as the principal therapeutic option for chronic hepatitis B (CHB). Treatment with entecavir (ETV), tenofovir disoproxil (TDF) and the later released tenofovir alafenamide (TAF) is highly effective at controlling hepatitis B virus (HBV) infection and, in the vast majority of patients, is well tolerated. No significant differences in viral suppression have been described among the different regimens, although an earlier achievement in biochemical response has been suggested first under TDF and recently under TAF. High barrier to resistance NAs rarely achieve hepatitis B surface antigen sero-clearance, and therefore should be maintained life-long in most cases. This has increased concerns about treatment-related toxicity, especially in patients under TDF with additional risk factors for kidney and bone impairment. TAF has shown a better bone and kidney safety profile than TDF, although it is not yet available worldwide due to its higher cost. Emergence of adverse events should be monitored since treatment-switch to ETV/TAF seems to be effective and safe in HBV mono-infected subjects. Finally, although an effective antiviral treatment leads to a clear improvement in clinical outcome of CHB patients; the risk of developing hepatocellular carcinoma (HCC) is not completely avoided with viral suppression. Whether tenofovir-based regimens provide any additional benefit over ETV in HCC prevention remains unclear and requires further investigation.